ANALYSIS OF CREEP PORE FORMATION IN LIQUID-PHASE SINTERED ALUMINA

Failure of ceramic materials used in high-temperature applications is initiated by the formation of creep pores. Thus, investigating the kin etics of creep pore formation, especially the evolution of their size distribution, is of key importance in obtaining an understanding of th e failure mechanisms. This investigation is concerned with recent prog ress in the characterization of creep pores in liquid-phase sintered a lumina by means of small-angle neutron scattering (SANS) techniques. I t is shown tl;at creep pores ranging from about 40 nm to >1 mu m are p resent even after the small amount of creep deformation at the end of primary creep. For the first time a strong correlation between the siz e of glass pockets and the creep pores has been determined. The result s give new insights into pore formation in liquid-phase sintered ceram ics. (C) 1997 Elsevier Science S.A.